Interaction of Salinity and Feed Protein Level on Growth ofPenaeus vannamel

An intensive 42-day growth trial conducted in ourdoor tanks with Penaeus vannamei (stocking weight of 5.3g, density of 30/m2) indicated that there was a significant interaction between salinity and protein level of the feed. In 46 ppt water, shrimp fed feed containing 45% protein grew faster (2.98%/day) than shrimp fed 35 and 25% protein rations (2.84 and 2.73%/day, respectively). At 12 ppt, growth of shrimp fed 35% feed was faster (3.23%/day) than growth of shrimp fed 25% protein feed (3.07%/day). Shrimp fed the 45% protein feed did not grow faster 3.14%/day) than shrimp fed 35 an 25% protein feeds. At each protein level, growth at 12 ppt was greater than at 46ppt. Survival was not affeted by either salinity or feed protein level and averaged 86%. Results indicate that nutritional requirements vary with culture salinity and suggest that use of higher protein feeds under hypersaline culture conditions may produce higher yields.